In latest versions 1.18.76/77 Hires gun-models remain on low quality. Rockets and other items show ok.
Had an old version 1.15.271 as complete backup where models were drawn correctly. Compared in both versions the settings, ini-file, and the ase/tga files in model folder. No discrepancies found, settings and files are identical in both versions.
A better picture showing the low res and hi res items.